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Alternatives

Products that do what langgraph-cassette does

Record once. Replay forever.

  1. 1
    LangWatch669

    Understand, measure and improve your LLMs

    2024 · langwatch.ai

  2. 2
    Langfuse771

    Open source tracing and analytics for LLM applications

    2023 · langfuse.com

  3. 3

    LLM application development, monitoring, and testing

    2024

  4. 4

    The low-code platform for testing AI apps

    2024

  5. 5

    Evaluate & optimize your LLM performance with DSPy

    2024

  6. 6
    Replay279

    Your time travel debugger

    2021

  7. 7

    Open Source LLM Engineering Platform

    2024

  8. 8
    Langdock294

    Create, deploy, test & monitor ChatGPT plugins in minutes

    2023

  9. 9
    traceAI273

    Open-source LLM tracing that speaks GenAI, not HTTP.

    Apr 2026 · github.com

  10. 10TT
  11. 11

    Ship AI apps with fewer surprises

    2024

  12. 12

    Instantly record and debug across your entire stack

    2023

  13. 13
    LangSmith349

    Build and deploy LLM applications with confidence

    2023

  14. 14YD

    If you've built any web-based app in the last 15 years, you probably used something like Datadog, New Relic, Sentry, etc. to monitor and trace your app, right? Why should it be different when the app you're building happens to be using LLMs? So today we're open-sourcing OpenLLMetry-JS. It's an open protocol and SDK, based on OpenTelemetry, that provides traces and metrics for LLM JS/TS applications and can be connected to any of the 15+ tools that already support OpenTelemetry. Here's the repo: https://github.com/traceloop/openllmetry-js A few months ago we launched…

    2024 · github.com

  15. 15

    Open-source LLM tracing for agent visibility

    Mar 2026 · breadcrumb.sh

  16. 16

    Get deep insights and evaluate your LLM application data

    2025

  17. 17CR

    I got tired of sharing AI demos with terminal screenshots or screen recordings. Claude Code already stores full session transcripts locally as JSONL files. Those logs contain everything: prompts, tool calls, thinking blocks, and timestamps. I built a small CLI tool that converts those logs into an interactive HTML replay. You can step through the session, jump through the timeline, expand tool calls, and inspect the full conversation. The output is a single self-contained HTML file — no dependencies. You can email it, host it anywhere, embed it in a blog post, and it works on mobile. Repo:…

    Mar 2026 · github.com

  18. 18RR
  19. 19LL

    Hey HN, I just built an experimental VSCode extension called LLM Debugger. It’s a proof-of-concept that lets a large language model take charge of debugging. Instead of only looking at the static code, the LLM also gets to see the live runtime state—actual variable values, function calls, branch decisions, and more. The idea is to give it enough context to help diagnose issues faster and even generate synthetic data from running programs. Here’s what it does: * Active Debugging: It integrates with Node.js debug sessions to gather runtime info (like variable states and stack traces). *…

    2025 · github.com

  20. 20

    A collection of production-ready reference architectures

    2023

  21. 21CA

    Hi HN! We’re been working hard on this low-code tool for rapid prompt discovery, robustness testing and LLM evaluation. We’ve just released documentation to help new users learn how to use it and what it can already do. Let us know what you think! :)

    2023 · chainforge.ai

  22. 22LO

    Hi HN! Langfuse is OSS observability and analytics for LLM applications (repo: https://github.com/langfuse/langfuse, 2 min demo: https://langfuse.com/video, try it yourself: https://langfuse.com/demo) Langfuse makes capturing and viewing LLM calls (execution traces) a breeze. On top of this data, you can analyze the quality, cost and latency of LLM apps. When GPT-4 dropped, we started building LLM apps – a lot of them! [1, 2] But they all suffered from the same issue: it’s hard to assure quality in 100% of cases and even to have a clear view…

    2023 · github.com

  23. 23PF

    Hey everyone, I'm Petr. I'm excited to share LangTale Playground (https://langtale.ai/playground), a first-of-its-kind tool enabling anyone to experiment with OpenAI function calls without coding. Born out of a hackathon project, it's now a part of our broader LangTale platform aimed at tackling common developer challenges with Language Learning Models (LLM). These include prompt integration, testing and debugging, version control, auditing, and usage/cost management. Here's our tech stack: Next.js by Vercel, Tailwind CSS, OpenAI, PlanetScale's Vitess database, and the…

    2023 · langtale.ai

  24. 24OO

    Hey HN, Nir, Gal and Tomer here. We’re open-sourcing a set of extensions we’ve built on top of OpenTelemetry that provide visibility into LLM applications - whether it be prompts, vector DBs and more. Here’s the repo: https://github.com/traceloop/openllmetry. There’s already a decent number of tools for LLM observability, some open-source and some not. But what we found was missing for all of them is that they were closed-protocol by design, vendor-locking you to use their observability platform or their proprietary framework for running your LLMs. It’s still early in the…

    2023 · github.com

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